ID   HSS2_SENVE              Reviewed;         370 AA.
AC   P60038;
DT   21-NOV-2003, integrated into UniProtKB/Swiss-Prot.
DT   21-NOV-2003, sequence version 1.
DT   03-AUG-2022, entry version 60.
DE   RecName: Full=Homospermidine synthase 2;
DE            Short=HSS2;
DE            EC=2.5.1.45;
OS   Senecio vernalis (Spring groundsel).
OC   Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC   Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae;
OC   asterids; campanulids; Asterales; Asteraceae; Asteroideae; Senecioneae;
OC   Senecioninae; Senecio.
OX   NCBI_TaxID=93496;
RN   [1]
RP   NUCLEOTIDE SEQUENCE, AND PROTEIN SEQUENCE OF 7-17; 151-159; 211-224 AND
RP   278-289.
RC   TISSUE=Root;
RX   PubMed=10611289; DOI=10.1073/pnas.96.26.14777;
RA   Ober D., Hartmann T.;
RT   "Homospermidine synthase, the first pathway-specific enzyme of
RT   pyrrolizidine alkaloid biosynthesis, evolved from deoxyhypusine synthase.";
RL   Proc. Natl. Acad. Sci. U.S.A. 96:14777-14782(1999).
RN   [2]
RP   NUCLEOTIDE SEQUENCE.
RX   PubMed=11117877; DOI=10.1016/s0031-9422(00)00267-3;
RA   Ober D., Harms R., Hartmann T.;
RT   "Cloning and expression of homospermidine synthase from Senecio vulgaris: a
RT   revision.";
RL   Phytochemistry 55:305-309(2000).
CC   -!- FUNCTION: Catalyzes the transfer of an aminobutyl unit from spermidine
CC       onto putrescine. The resulting polyamine homospermidine is a precursor
CC       in the biosynthesis of pyrrolizidine alkaloids.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=putrescine + spermidine = propane-1,3-diamine + sym-
CC         homospermidine; Xref=Rhea:RHEA:11236, ChEBI:CHEBI:57484,
CC         ChEBI:CHEBI:57811, ChEBI:CHEBI:57834, ChEBI:CHEBI:326268;
CC         EC=2.5.1.45;
CC   -!- COFACTOR:
CC       Name=NAD(+); Xref=ChEBI:CHEBI:57540;
CC   -!- PATHWAY: Alkaloid biosynthesis; pyrrolizidine alkaloid biosynthesis.
CC   -!- SUBUNIT: Homotetramer.
CC   -!- TISSUE SPECIFICITY: Expressed in roots.
CC   -!- PTM: The N-terminus is blocked.
CC   -!- SIMILARITY: Belongs to the deoxyhypusine synthase family.
CC       {ECO:0000305}.
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DR   AlphaFoldDB; P60038; -.
DR   SMR; P60038; -.
DR   PRIDE; P60038; -.
DR   SABIO-RK; P60038; -.
DR   UniPathway; UPA00329; -.
DR   GO; GO:0050514; F:homospermidine synthase (spermidine-specific) activity; IEA:UniProtKB-EC.
DR   GO; GO:0008612; P:peptidyl-lysine modification to peptidyl-hypusine; IEA:InterPro.
DR   Gene3D; 3.40.910.10; -; 1.
DR   InterPro; IPR002773; Deoxyhypusine_synthase.
DR   InterPro; IPR036982; Deoxyhypusine_synthase_sf.
DR   InterPro; IPR029035; DHS-like_NAD/FAD-binding_dom.
DR   PANTHER; PTHR11703; PTHR11703; 1.
DR   Pfam; PF01916; DS; 1.
DR   SUPFAM; SSF52467; SSF52467; 1.
DR   TIGRFAMs; TIGR00321; dhys; 1.
PE   1: Evidence at protein level;
KW   Direct protein sequencing; NAD; Transferase.
FT   CHAIN           1..370
FT                   /note="Homospermidine synthase 2"
FT                   /id="PRO_0000134518"
SQ   SEQUENCE   370 AA;  40733 MW;  F4A65775E749DE5C CRC64;
     MAESNKEAID SARSNVFKES ESLEGTCAKI GGYDFNNGID HSKLLKSMVS TGFQASNLGD
     AMIITNQMLE WRLSHDEVPE HCSEEEKKNR ESVKCKIFLG FTSNLISSGV RETICYLAQH
     RMVDVLVTTT GGIEEDFIKC LASTYKGKFS LPGADLRSKG LNRIGNLIVP NDNYIKFEDW
     IIPIFDQMLI EQKTQNVLWT PSRMIARLGK EINNETSYLY WAYKNNIPVF CPSITDGSIG
     DMLYFHSVSN PGPGLVVDIV QDVIAMDNEA VHASPQKTGI IILGGGLPKH HICNANMMRN
     GADFAVFINT AQEYDGSDSG ARPDEAVSWG KISSTGKAVK VHCDATIAFP LLVAETFAVK
     KEKASKVNGF